The present invention relates to an antislip device for footwear such as golf shoes, particularly an antislip device for footwear that is easy to mount and dismount and that can be reliably attached and detached.
Concerning antislip devices for golf shoes, spikes made of metal or ceramic have heretofore been used, but antislip devices made of synthetic resin have come into wide use for prevention of damage to greens and the like and for improved wearing feel. Such antislip devices made of synthetic resin are likely to wear easily as compared with those made of metal, so that an externally threaded raised portion made of metal or synthetic resin is formed on the back of the antislip device, while an internally threaded portion made of metal adapted to be threadedly fitted thereto is formed on the sole of a golf shoe, thereby making the antislip device removably mountable and exchangeable.
In the mounting and dismounting of the conventional antislip devices, however, in either of the attachment and detachment cases, a mounting/dismounting tool for turning the antislip device has to be used to turn it by as much amount as required; thus the operation of reliably threadedly mounting and dismounting all of the many antislip devices for a pair of golf shoes is troublesome. Furthermore, in the case where the externally and internally threaded portions, respectively, are made of metal, long-term use results in rusting to make the screws unturnable to the extent that removal of the screws is impossible or difficult, forcible removal tending to cause personal injury or damage or the like to the antislip mechanism. Further, in the case where the externally threaded portion is made of synthetic resin, improper tightening of the threaded portions could cause damage to the threads of the male screw or the stem of the male screw, resulting in the antislip device not being fully threadedly fixed and allowing it to come off during use. Further, if both of the internally and externally threaded portions, respectively, are made of synthetic resin, the threaded portions are likely to loosen and improper tightening damages one or both of their threads to the extent that the antislip device is likely not to be fully fixed; thus, such arrangement is impossible.
The present invention, which has been accomplished in view of the above problems inherent in the prior art, is to provide an antislip device for footwear that can be easily mounted and dismounted and reliably attached and detached.
(1) An antislip device for footwear according to the present invention is;
an antislip device for footwear, comprising a holder used by being fixed to the bottom of footwear, and an antislip body to be held in said holder, said antislip body having an antislip portion that, when the antislip body is held in the holder fixed to the bottom of the footwear, contacts a surface to be trod by the bottom of the footwear so as to prevent the footwear from slipping relative to said surface,
said holder and said antislip body have a holder-associated fitting portion and an antislip body-associated fitting portion, respectively, that fit together,
said holder-associated fitting portion and said antislip body-associated fitting portion have a transverse support mechanism capable of preventing a relative movement between them in a direction orthogonal to the direction of fit when said antislip body-associated fitting portion fits in said holder-associated fitting portion,
of such things as a slip-off preventive recess and a slip-off preventive projection capable of fitting in said slip-off preventive recess when the holder-associated fitting portion and the antislip body-associated fitting portion are fitted together, one is possessed by the holder and the other by the antislip body,
either said slip-off preventive recess constituting portion or said slip-off preventive projection is urged in a direction in which it can be fitted to the other, said slip-off preventive recess and said slip-off preventive projection being shaped such that when they are relatively moved in a direction in which they are fitted together, they can be fitted together and when they are relatively moved in the opposite direction, their fitting is not canceled,
one or more insert receiving portions being provided in which fit-canceling inserts can be inserted when the antislip body is in the state of being held in the holder fixed to the bottom of the footwear, said urged slip-off preventive recess constituting portion or slip-off preventive projection canceling the fit between the two by a force opposite in direction to said urging force that it receives from the inserts directly or through some other portion when the fit-canceling inserts are sufficiently inserted in the insert receiving portions.
The holder may be suitably formed of synthetic resin, metal, ceramic material, or a combination thereof. The holder is used by being fixed to the bottom of footwear. For example, it may be used by being embedded in and fixed to a synthetic resin footwear bottom (for example, a shoe sole, particularly a sport shoe sole, such as a golf shoe sole). Besides this, it may be formed by integral molding in such a footwear bottom, or may be formed by integral molding in the base portion of a footwear bottom, so that it is used in the state of being exposed to the bottom surface of the footwear bottom.
The antislip portion may be suitably made of synthetic resin, metal, ceramic material, or a combination thereof. Concerning the configuration of to the antislip portion, examples thereof are a group of small projections, a group of ridges, a linearly radially disposed ridge, a spirally radially disposed ridge, for example, a substantially circular plate-like body, which projects to the bottom surface side of the footwear bottom when the antislip body is held in the holder fixed to the footwear bottom.
Concerning the synthetic resin used for the holder and the antislip body, for example, nylon resin (for example, 66 nylon resin), urethane resin may be employed.
Either the holder-associated fitting portion or the antislip body-associated fitting portion may be a fitting projection and the other a fitting recess. For example, the antislip body may comprise a plate-like antislip portion having an antislip projection on the front and a pillar-like antislip body-associated fitting portion (fitting projection) erected on the back of the antislip portion, while the holder may comprise a hole-like holder-associated fitting portion (fitting recess) in which said antislip body-associated fitting portion fits. Further, for example, the holder may have a pillar-like holder-associated fitting portion (fitting projection) erected thereon, while the antislip body may have an antislip body-associated fitting portion (fitting recess) in which said holder-associated fitting portion fits in.
The transverse support mechanism may be constituted, for example, such that one of the outer and inner peripheral portions that support each other in a direction orthogonal to the direction of fit upon fitting between the holder-associated fitting portion and the antislip body-associated fitting portion is provided in the holder-associated fitting portion at two or more places or continuously in the direction of fit, and the other in the antislip body-associated fitting portion. Examples of such combinations of the outer and inner peripheral portions are a cylindrical inner peripheral surface and a cylindrical outer peripheral surface; an inner peripheral surface and an outer peripheral surface that are polygonal in cross section (for example, regular polygonal in cross section); an inner peripheral surface and an outer peripheral surface that are elliptic in cross section. (In each case, there may be one or more discontinuous portions disposed peripherally or in the direction of fit. For example, if the cylindrical inner peripheral surface or cylindrical outer peripheral surface is peripherally discontinuous, this results in one or more arcuate inner peripheral surface or arcuate outer peripheral surfaces that are continuous in the direction of fit.) Besides these, another example is a combination of one of said inner and outer peripheral surfaces and the other that is replaced by a required number of ridges that extend substantially in the direction of fit and whose edges extend along the surface.
The transverse support mechanism may be composed of a cylindrical inner peripheral surface and a cylindrical outer surface (each may have one or more discontinuous portions disposed peripherally or in the direction of fit) such that rotation of the antislip body relative to the holder around the axis extending in the direction of fit is allowed in consideration of protection of the portion of turf or the like that is to be trod, control of wear of the antislip portion of the antislip body, etc. In addition, for example, in order to exert an advantageous antislip function as much as possible in games such as golf, antislip devices that are rotatable and antislip devices that are nonrotatable may be used, mixedly disposed according to the positions of the antislip devices on the footwear bottom.
It is desirable that this antislip device for footwear have a direction-of-fit support mechanism that supports such that when the antislip body-associated fitting portion is fitted to the holder-associated fitting portion, the depth of fitting is prevented from exceeding a certain limit.
The direction-of-fit support mechanism may be constituted, for example, by providing a holder-associated support portion and an antislip body-associated support portion that contact each other when the depth of fitting reaches a certain limit when the antislip body-associated fitting portion is fitted to the holder-associated fitting portion and that support each other in the direction of fit or in a direction having a component of the direction of fit.
Examples of the holder-associated support portion and antislip body-associated support portion will be given as to a case in which the antislip body comprises a plate-like antislip portion having an antislip projection on the front, and a pillar-like antislip body-associated fitting portion (fitting projection) erected on the back of the antislip portion while the holder comprises a bottomed hole-like holder-associated fitting portion (fitting recess) in which said antislip body-associated fitting portion fits in. In one example, the holder-associated support portion is the peripheral edge of the opening in the holder-associated fitting portion (fitting recess) while the antislip body-associated support portion is the peripheral edge of the antislip body-associated fitting portion (fitting projection) on the back of the antislip portion, and in another example, the antislip body-associated support portion is the front end of the antislip body-associated fitting portion (fitting projection) while the holder-associated support portion is the bottom of the holder-associated fitting portion (fitting recess).
In addition, in place of such holder-associated support portion, a support portion that supports, and is supported by, the antislip body-associated support portion may be provided in the footwear bottom.
Concerning the slip-off preventive recess, for example, one or more recesses substantially corresponding in size to the slip-off preventive projection may be provided. Besides this, it may, for example, be a groove endlessly extending around the axis extending in the direction in which the antislip body-associated fitting portion is fitted to the holder-associated fitting portion. Further, the slip-off preventive projection may be replaced by one or more projections substantially corresponding in size to the slip-off preventive recess. Besides this, it may, for example, be a projection endlessly extending around the axis extending in the direction in which the antislip body-associated fitting portion is fitted to the holder-associated fitting portion. If said transverse support mechanism, as in the case of being composed of the cylindrical inner and outer peripheral surfaces, allows relative rotation around the axis of the direction of fit with the holder-associated fitting portion and antislip body-associated fitting portion fitted together, it is desirable that the slip-off preventive recess be an endlessly continuous groove as described above or that the slip-off preventive projection be an endlessly continuous edge as described above, in order to enable the slip-off preventive projection to fit in the slip-off preventive recess irrespective of the angle of rotation between them. In this case, however, the term xe2x80x9cendlesslyxe2x80x9d does not necessarily mean xe2x80x9cperfectly endlessly;xe2x80x9d thus, the presence of a discontinuous portion somewhere is allowed provided that the slip-off preventive projection is allowed to fit in the slip-off preventive recess irrespective of the angle of rotation between them.
The urging force exerted in a direction in which either the slip-off preventive recess constituting portion or the slip-off preventive projection receives said force and is fitted to the other, is elastic. That is, it can be arranged that either the slip-off preventive recess constituting portion or the slip-off preventive projection receives an elastic force in a direction in which it can be fitted to the other. For example, such urging may be effected by the elasticity possessed either by the slip-off preventive projection or by the slip-off preventive recess constituting portion, or it may be effected by the elasticity of an elastic member, such as a compression spring or tension spring, subjected either to the slip-off preventive projection or to the slip-off preventive recess constituting portion. Alternatively, it may be effected by the elasticity possessed either by a portion having the slip-off preventive projection or by a portion having the slip-off preventive recess constituting portion (for example, it may be effected by the elasticity possessed by the cantilever-like portion).
Concerning the slip-off preventive recess and slip-off preventive projection, in order to attain a shape that ensures that the fit is not canceled in the case of a relative movement taking place in a direction opposite to the direction in which the antislip body-associated fitting portion is fitted to the holder-associated fitting portion, that is, in a direction to cancel the fit, it is possible to employ a shape, for example, such that the angle between the surfaces in the fitting innermost regions in both of the slip-off preventive recess and the slip-off preventive projection and the fit-canceling direction is an acute angle or substantially right angle. Concerning a shape that allows the antislip body-associated fitting portion to be fitted to the holder-associated fitting portion in the case of a relative movement taking place in the direction that allows fitting, it is possible to employ a shape, for example, such that the angle between the surface in a region opposite to the fitting innermost region in the slip-off preventive projection and the direction of fit is an obtuse angle. In other arrangements also, for example, in the case of relative movement taking place in the fit-canceling direction, the fit will not be canceled if the side urged in a direction in which either the slip-off preventive projection or the slip-off preventive recess constituting portion is fitted to the other, tends to move in the direction of the urging force.
It is desirable that the fit between the slip-off preventive recess and slip-off preventive projection be effected at two or more places. The reason is that even if the fit at one place should be canceled by some cause or other against the user""s will, falling-off of the antislip body from the holder can be prevented.
Concerning the provision of the insert receiving portion, there are various cases including one in which it is provided in the antislip body alone, another in which it is provided in the holder alone, and another in which it extends through the antislip body to reach the holder. In the case where the insert receiving portion extends through the antislip body to reach the holder and the antislip body is allowed to rotate relative to the holder around the axis of the direction of fit with the holder-associated fitting portion and the antislip body-associated fitting portion fitted together, the insert receiving portion sometimes coincides between the antislip body and the holder and sometimes does not, depending on the angle of rotation of the antislip body. Thus, in this case, in order to sufficiently insert the insert in the fit-canceling insert in the insert receiving portion, the angle of rotation of the antislip body will be adjusted as needed. In that case, if the position of the insert receiving portion in the holder is indicated at a visible position in the holder or the footwear bottom, this is convenient for adjusting the rotation angle position of the antislip body. The position of the insert receiving portion may be shown by symbols, such as arrows, figures, letters or a combination thereof, by a planar indication using a paint or the like, or by unevenness or the like.
Concerning the shape of the insert receiving portion, holes or the like of circular or quadrangular cross section may be suitably employed and, though not particularly restricted, the cross sectional area of the insert receiving portion (particularly, the cross sectional area of the insert receiving port) is preferably as small as possible. This is for the purpose of preventing undesirable occurrences in which in the period of use until replacement of the antislip body becomes necessary, various pointed and other substances lying on the ground, floor surfaces or the like accidentally enter the insert receiving portion to cancel the fit between the slip-off preventive recess and the slip-off preventive projection or to clog the insert receiving portion. In order to prevent such undesirable occurrences more reliably, it is desirable that the insert receiving portion (desirably, the insert receiving port of the insert receiving portion) be closed by a removable or destroyable cover. Such cover is not necessarily required to effect perfect closure.
The insert receiving portion is required to have a position and a shape such that the insertion of the fit-canceling insert exerts a force that is opposite in direction to said urging force on the urged slip-off preventive recess constituting portion or urged slip-off preventive projection directly or through another portion and that is capable of moving the urged slip-off preventive recess constituting portion or slip-off preventive projection in the direction in which the fit between the two is canceled.
Concerning the arrangement in which the urged slip-off preventive recess constituting portion or urged slip-off preventive projection receives a force opposite in direction to said urging force directly or through another portion as a results of the fit-canceling insert being inserted in the insert receiving portion, the following arrangement may be cited: an arrangement in which, for example, the slip-off preventive projection or slip-off preventive recess constituting portion itself, the elastic member that urges the slip-off preventive projection or slip-off preventive recess constituting portion, or the portion having the slip-off preventive projection or slip-off preventive recess constituting portion (for example, the cantilever-like portion) has a portion inclined in the direction of said urging force with respect to the direction of fit between the holder and antislip body when the slip-off preventive projection and slip-off preventive recess are fitted together, so that said inclined portion receives a force opposite in direction to said urging force when pressed by the insert.
The shape of the fit-canceling insert is required to be such that the insert can be inserted in the insert receiving portion to a sufficient depth. In the case of an arrangement in which two or more urged slip-off preventive projections or two or more urged slip-off preventive recess constituting portions are simultaneously fitted to the slip-off preventive recesses or slip-off preventive projections, it is desirable that the fit-canceling insert be formed in, for example, a bifurcated shape (or a three-branched or more-branched shape) and the two or more urged slip-off preventive projections or two or more urged slip-off preventive recess constituting portions can be simultaneously moved in the fit-canceling direction.
If the antislip body-associated fitting portion of the antislip body is sufficiently fitted to the holder-associated fitting portion of the holder fixed to the footwear bottom, the slip-off preventive recess constituting portion or slip-off preventive projection is urged until the slip-off preventive projection fits in the slip-off preventive recess and cancellation of the fit between the holder-associated fitting portion and the antislip body-associated fitting portion is prevented so that the antislip body is fixedly held by the holder.
The transverse support mechanism prevents displacement and inclination of the antislip body-associated fitting portion relative to the holder-associated fitting portion in a direction orthogonal to the direction of fit. This prevents undesirable occurrences including the antislip body being unstably held in the footwear bottom to fail to exert the sufficient antislip effect, breakage or wear occurring in the holder-associated fitting portion or antislip body-associated fitting portion, and the hold of the antislip body provided by the holder being canceled during use to result in the antislip body falling off.
In order to release the antislip body from the holder, a fit-canceling insert is sufficiently inserted in the insert receiving portion. Thereby, the insert exerts a force in the urged slip-off preventive recess constituting portion or slip-off preventive projection directly or through another portion, said force being opposite in direction to said urging force, thereby moving the urged slip-off preventive recess constituting portion or slip-off preventive projection in a direction in which the fit between the two is canceled, thus canceling the fit between the slip-off preventive recess and the slip-off preventive projection, so that the antislip body can be removed from the holder.
The mounting and dismounting of the antislip body on and from the holder can be effected in a simple operation, without requiring force and trouble to tighten screws with great force for fixing against loosening or turning them backward with great force for removal as in the case of using a screw mechanism. Therefore, mounting and dismounting are easy for women, old people, children, etc. Further, unlike screws made of metal, there is no danger of prolonged use resulting in rusting to make removal impossible or difficult, a fact which is likely to cause injuries to the user or breakage or the like to the antislip mechanism, or unlike screw threads made of synthetic resin, there is no danger that tightening leads to breakage of the screw or the screw stem, which, in turn, causes the antislip body to fail in being threadedly sufficiently fixedly held and to come off during use. Furthermore, since the holder and the antislip body can both be made of synthetic resin, the effectiveness is high in reducing the weight of the entire footwear including the fittings, as compared with the prior art in which at least the holder is made of metal.
(2) The footwear antislip device of (1) may be such that;
the antislip body-associated fitting portion is a fitting projection having a cylindrical outer peripheral surface that may have one or more circumferentially disposed discontinuous portions, while the holder-associated fitting portion is a fitting recess having a cylindrical inner peripheral surface that may have one or more circumferentially disposed discontinuous portions, said cylindrical outer and inner peripheral surfaces constituting the transverse support mechanism.
In this case, irrespective of the angle around the axis extending in the direction of fit in which the antislip body is fitted to the holder, the antislip body-associated fitting portion can be fitted to the holder-associated fitting portion to fixedly hold the antislip body in the holder and the antislip body is allowed to rotate relative to the holder.
In addition, a recessed portion and a raised portion that fit together when the antislip body is held in the holder may be provided in the holder and the antislip body, whereby the rotation of the antislip body relative to the holder when the antislip body is held in the holder can be made impossible.
(2-1) The footwear antislip device of (2) may be such that;
when the holder-associated fitting portion and antislip body-associated fitting portion are fitted together, they are relatively turnable around the axis extending in the direction of fit, and the antislip body-associated fitting portion has a circumferentially endlessly continuous groove-like slip-off preventive recess while the holder has one or more slip-off preventive projections capable of fitting in said slip-off preventive recess.
Since the slip-off preventive projection is allowed to fit in the slip-off preventive recess irrespective of the angle of rotation between the holder-associated fitting portion and the antislip body-associated fitting portion, the operation of fitting the antislip body-associated fitting portion to the holder-associated fitting portion so as to attach the antislip body to the holder is easy.
(2-2) The footwear antislip device of (2-1) may be such that;
the holder has one or more cantilever-like portions each having a base portion on the fitting port side of the holder-associated fitting portion and a radially inwardly projecting slip-off preventive projection at the front end extending toward the innermost fitting region,
said cantilever-like portion having an inner surface that is radially inwardly inclined toward the innermost fitting region when the slip-off preventive projection is fitted in the slip-off preventive recess, the arrangement being such that when the fit-canceling inserts are sufficiently inserted in the insert receiving portions, the inserts press and radially outwardly elastically deform the inner surfaces thereof, thereby canceling the fit between the slip-off preventive projection and the slip-off preventive recess.
The antislip body can be attached to the holder irrespective of the angle of rotation between the holder-associated fitting portion and the antislip body-associated fitting portion. Further, sufficiently inserting the fit-canceling insert in the insert receiving portion results in the insert pressing the inner surface thereof to radially outwardly elastically deform the cantilever-like portion, thereby canceling the fit between the slip-off preventive projection and the slip-off preventive recess, so that the antislip body can be detached from the holder. In that case, a force in a direction in which the insert is released from the insert receiving portion can be applied to the insert by the inner surface of the urged cantilever-like portion. Further, if this pressure force on the inner surface is canceled, the cantilever-like portion and the slip-off preventive projection are restored to their original positions.
(2-3) The footwear antislip device of (2) may be such that when the holder-associated fitting portion and the antislip body-associated fitting portion are fitted together, they are relatively rotatable around the axis extending in the direction of fit,
the holder has a slip-off preventive projection while the antislip body-associated fitting portion has a slip-off preventive recess, said slip-off preventive projection being urged in a direction in which it can fit in said slip-off preventive recess,
the insert receiving portion comprises an antislip body-associated insert receiving portion extending through the antislip body and a holder-associated insert receiving portion possessed by the holder,
the arrangement being such that with the rotation angle position of the antislip body-associated insert receiving portion coinciding with the position of the holder-associated insert receiving portion, the fit-canceling insert inserted in said antislip body-associated insert receiving portion is sufficiently inserted in the holder-associated insert receiving portion, thereby making it possible to cancel the fit between the slip-off preventive projection and the slip-off preventive recess.
This footwear antislip device may be such that the number of antislip body-associated insert receiving portions is greater than the number of holder-associated insert receiving portions, and the antislip body has two or more angles of rotation relative to the holder such that the position of the antislip body-associated insert receiving portion coincides with the position of the holder-associated insert receiving portion, the cancellation of the fit between the slip-off preventive projection and the slip-off preventive recess is made possible, which, in turn, makes possible the cancellation of the fit between the antislip body-associated fitting portion and the holder-associated fitting portion.
In this case, a smaller angle of rotation is sufficient to align the angle of rotation of the antislip body-associated insert receiving portion with the position of the holder-associated insert receiving portion.
The footwear antislip device has two or more rotation angle positions of the antislip body relative to the holder that allow cancellation of the fit between the antislip body-associated fitting portion and the holder-associated fitting portion, and it is preferable that the central angles at the respective rotation angle positions be equal or substantially equal. That is, where the number of rotation angle positions is represented by n, the central angle is approximately (360/n) degrees. In this case, the angle of rotation required to make the rotation angle position of the antislip body-associated insert receiving portions coincide with the position of the holder-associated insert receiving portions is always at a minimum. As a preferred example, the footwear antislip device has two holder-associated insert receiving portions spaced a central angle of 180 degrees apart at a given radial position and four antislip body-associated insert receiving portions spaced a central angle of 90 degrees at the same given radial position as in the holder-associated insert receiving portion. In this case, in any of the four antislip body-associated insert receiving portions, inserts are simultaneously sufficiently inserted in the two holder-associated insert receiving portions and the antislip body-associated insert receiving portions that coincide with them, whereby the fit between the slip-off preventive projection and the slip-off preventive recess can be canceled.
(3) The footwear antislip device of said (1), (2), (2-1), (2-2) or (2-3) may be such that the antislip portion has a substantially plate-shape portion so that when the antislip body is held in the holder, the outer periphery of the antislip body and the outer periphery of the holder press against each other throughout the periphery.
In order to effect cancellation of the fit between the antislip body-associated fitting portion and the holder-associated fitting portion, it is necessary to sufficiently insert the fit-canceling insert in the insert receiving portion through said opening to cancel the fit between the slip-off preventive projection and the slip-off preventive recess. However, if particles of stone, sand or earth, grass, dust, dirt, etc. enter between the antislip body and the holder, there is the danger of the slip-off preventive recess constituting portion or the slip-off preventive projection failing to operate or of it becoming impossible to insert the fit-canceling insert in the insert receiving portion to effect cancellation of the fit between the slip-off preventive projection and the slip-off preventive recess, or the danger of the intrusive extraneous substances clogging the fitting region between the antislip body-associated fitting portion and the holder-associated fitting portion to make impossible cancellation of the fit itself between the antislip body-associated fitting portion and the holder-associated fitting portion.
In the case of this footwear antislip device, in the state in which the footwear is used, that is, in the state in which the antislip body is held in the holder fixed in the footwear bottom and is ready to tread on the ground, the outer peripheries of the antislip body and holder are pressed against each other throughout the periphery, so that particles of stone or the like are prevented from entering therebetween from the outer peripheries of the antislip body and holder; therefore, cancellation of the fit between the slip-off preventive projection and the slip-off preventive recess and cancellation of the fit between the antislip body-associated fitting portion and the holder-associated fitting portion can be effected more reliably.
Ensuring that the outer peripheries of the antislip body and holder are pressed against each other throughout the periphery with the antislip body held in the holder, is made possible by determining the dimensional relationship such that, for example, a compressive force acts between the outer peripheries of the antislip body and holder upon fitting between the slip-off preventive projection and the slip-off preventive recess owing to the fit between the antislip body-associated fitting portion and the holder-associated fitting portion.
It is preferable that the outer peripheries of the holder and antislip body be pressed against each other in an annular surface region or circumferential region that is rotation-symmetrical with respect to the axis of the direction of fit. In the case of the annular surface region, it may be an annular flat region normal to said axis, an annular inclined flat region inclined at a given angle with respect to said axis, an annular curved region, or the like.
Further, it may be arranged that the outer peripheries of the antislip body and holder are pressed against each other throughout the periphery with the outer periphery of the antislip body externally covering the outer periphery of the holder so that entry of particles of stone, sand or earth, grass, dust, dirt, etc. can be prevented more effectively.
In addition, in the case where the outer periphery of the antislip body is positioned outwardly of the outer periphery of the holder, it may be arranged that the outer periphery of the antislip body is pressed against the bottom surface of the footwear bottom throughout the periphery with the antislip body held in the holder fixed to the footwear bottom to prevent fine particles of stone or sand from entering between the antislip body and the holder. In this case, however, in order to produce a given degree of pressing force always between the outer periphery of the antislip body and the bottom surface of the footwear bottom, it is required that the accuracy of the positional relationship between the holder and the bottom surface of the footwear bottom be high to a given degree or above.
(4) The footwear antislip device of said (1), (2), (2-1), (2-2), (2-3) or (3) may be such that;
the insert receiving portion has an opening that opens to a surface to be trod by the bottom of the footwear when the antislip device is attached to the bottom of the footwear to be ready for use, through which opening the fit-canceling insert can be inserted in the insert receiving portion,
said opening having a valve flap that is pushed open toward the insert receiving portion by inserting said insert in said insert receiving portion and that is restored to its original position by extracting said insert from said insert receiving portion, said opening being closed or substantially closed by said valve flap.
For cancellation of the fit between the antislip body-associated fitting portion and the holder-associated fitting portion, it is necessary to insert the fit-canceling insert in the insert receiving portion through said opening. If, therefore, fine particles of stone, sand or earth, grass, dirt or the like enter the insert receiving portion through said opening to clog it to make it impossible to insert the insert, the fit between the antislip body-associated fitting portion and holder-associated fitting portion cannot be canceled, so that the antislip body cannot be released from the holder. In the case of this footwear antislip device, however, said opening in the insert receiving portion is closed or substantially closed by a valve flap that can be pressed open toward the insert receiving portion by the insert being inserted in the insert receiving portion and that can be restored to its original portion by said insert being extracted from the insert receiving portion, thereby preventing a danger that it becomes impossible to insert the insert as the insert receiving portion is clogged; thus, fit-cancellation can be effected more reliably. Further, as compared with the case of the insert receiving portion being closed by a breakable cover, the insert is less liable to be damaged when inserted in the insert receiving portion. Further, when fine particles of stone, sand earth or the like are finding their way into the insert receiving portion by pressing the valve flap inward, these particles can be expelled outward by the restoring force of the valve flap.
The term xe2x80x9csubstantially closedxe2x80x9d refers to a state in which, for example, there is a slight clearance between the inner periphery of the opening and the outer periphery of the valve flap.
The valve flap is preferably made of a material that can be restored by its own elasticity. Examples thereof are polyurethane resin, polypropylene resin, and acrylonitrile-butadiene-styrene copolymer resin. The antislip body is preferably made by integral molding of synthetic resin together with the valve body.
(4-1) The footwear antislip device of (4) may be such that the insert receiving portion comprises an antislip body-associated insert receiving portion extending through the antislip body and a holder-associated insert receiving portion possessed by the holder, the opening in the antislip body-associated insert receiving portion has a valve flap, the arrangement being such that when the insert is inserted in the insert receiving portion, said valve body elastically presses the insert in the vicinity of the opening.
Since the valve flap elastically presses the insert in the vicinity of the opening when the insert is inserted in the insert receiving portion to cancel the fit between the slip-off preventive projection and the slip-off preventive recess, the valve flap of the antislip body can be kept pressing and holding the insert and the antislip body can be released along with the insert by moving the insert in the direction of release when the antislip body is to be released from the holder. Particularly in the case of the footwear antislip device of (2-2), the inner surface of the urged cantilever-like portion can apply a force to the insert in a direction in which the insert is released from the insert receiving portion, so that release of the antislip body is easier.
(5) The footwear antislip device of said (1), (2), (2-1), (2-2), (2-3), (3), (4) or (4-1) is preferably such that the antislip portion of the antislip body is made of relatively soft material, while the slip-off preventive recess and the slip-off preventive projection are made of relatively rigid material.
Making the antislip portion of a relatively soft material (for example, polyurethane resin) contributes much to prevention of damage to greens and building floors and to improved wearing feel, while making the slip-off preventive recess and slip-off preventive projection of a relatively rigid material (for example, nylon resin or metal, or where elasticity is not required, ceramic material or the like) prevents undesirable occurrences in which an unexpected force acts during use to cancel the fit between the slip-off preventive recess and the slip-off preventive projection or in which the slip-off preventive recess or the slip-off preventive projection wears out so that the fit therebetween is accidentally canceled.
(5-1) The footwear antislip device of said (2-1), (2-2) or (2-3) is preferably such that the antislip portion of the antislip body is made of relatively soft material, while the antislip body-associated fitting portion and the holder are made of relatively rigid material.
In this case, as in the case of said (5), the antislip device contributes to prevention of damage to greens and building floors and to improved wearing feel, and prevents undesirable occurrences in which an unexpected force acts during use to cancel the fit between the slip-off preventive recess and the slip-off preventive projection or in which the slip-off preventive recess or the slip-off preventive projection wears out so that the fit therebetween is accidentally canceled.
(5-2) The footwear antislip device of said (5) or (5-1) may be such that the antislip body is an integral combination of a pillar-like body of relatively rigid material whose one end has lateral extensions and whose other end constitutes an antislip body-associated fitting portion, and an antislip portion of relatively soft material covering said lateral extensions of said pillar-like body.
Such antislip portion can be produced, for example, by molding and solidifying a relatively soft synthetic resin material (for example, polyurethane resin) in such a manner as to cover the lateral extensions of the pillar-like body produced in advance of a relatively rigid material (for example, nylon resin, metal, ceramic material). In this case, such extension may be laterally extended, for example, throughout the periphery (for example, in the form of a circular plate or a polygon); however, in order to ensure the integration of the pillar-like body and the antislip portion, it is preferable that the extensions be laterally extended in some directions (2 directions, 3 directions, 4 directions, etc.) and that the relatively soft synthetic resin material fill the space between the lateral extensions and solidify therein. In the case where they laterally extend in some directions, it is preferable that the lateral extensions be provided at intervals of an equal central angle. Further, the integration of the pillar-like body and the antislip portion may be ensured by providing axial through-holes in the lateral extensions so that the relatively soft synthetic resin material fills said through-holes and solidifies therein.
(6) The footwear of the present invention includes said footwear antislip device described in said (1), (2), (3) or(4) with a holder fixed in the footwear bottom.
(7) The fit-canceling device of the present invention comprises a grip, and two or more inserts extending in parallel with each other from said grip. If it is necessary to simultaneously insert inserts in a plurality of insert receiving portions parallel with the axis of the direction of fit in order to cancel the fit between the slip-off preventive projection and the slip-off preventive recess so as to separate the holder and the antislip body from each other, the user, griping the grip of the fit-canceling tool having a required number of inserts projecting in parallel with each other in an arrangement corresponding to the arrangement of the insert receiving portions, simultaneously inserts the inserts in the plurality of insert receiving portions. Thereby, the fit of all of the two or more slip-off preventive projections and slip-off preventive recesses can be simultaneously canceled to separate the holder and the antislip body from each other.
The inserts may be, for example, a linear bar in shape, but it goes without saying that they should correspond in shape to the insert receiving portions of the intended footwear antislip device.
The material and shape of at least the insert portions of this fit-canceling tool are preferably such that the insertion and extraction of the inserts in and from the insert receiving portions of an intended footwear antislip device can be effected within the limit of the elasticity of the material. The reason is that if the inserts are deformed when they are inserted or extracted, the inserts become unsuitable for reuse.
The antislip body of the footwear antislip device may have at least its central portion projected toward a surface to be trod by the footwear bottom when it is used by being attached to the holder fixed in the footwear bottom and may have projections that are discontinuous around the circumference with the direction-of-fit axis taken as the centerline (which projections likewise project toward the surface to be trod by the footwear bottom, such as circumferentially spaced small projections or substantially radial ridges). In that case, this fit-canceling tool has a plate-like portion in its grip, which plate-like portion has a turning recess in which said at least central portion of the antislip body fits, and upon fitting, the peripheral edge of said turning recess in the grip is allowed to be positioned between said circumferentially discontinuous projections, and by turning the grip around the direction-of-fit axis of the antislip body, the peripheral edge of said recess is caused to act on the projections of the antislip body to turn the antislip body, held in the holder, through an optional angle; thus, the problem of wear of the projections of the antislip body, etc. can be coped with.